The present invention relates to novel methods for preparing a resinous material suitable for use in hair sprays, and to the novel hair-holding resinous material created thereby. In addition, it relates to hair-holding compositions such as hair sprays, and the like.
Resinous materials for use in hair sprays must satisfy several requirements. In terms of functionality, materials are sought which deposit from solution, and preferably from alcohol solution, to form a non-tacky, non-greasy film which is unaffected by high humidity and which helps retain a curl when sprayed onto hair. In terms of appearance, it is also desirable that the solution be clear and that the film deposited therefrom be clear so that it does not appreciably alter the appearance and color of the hair. Finally, the deposited film should be easily removable from hair with a shampoo.
U.S. Pat. No. 2,440,555 to Omohundro et al. discloses alcoholic, resin-containing hair treatment solutions in which the resin is an abietic ester, such as ethyl abietate and ethylene glycol ester of abietic acid, or a hydrogenated abietic ester such as hydrogenated methyl abietate. It further discloses that these solutions form a thin protective non-tacky adhesive film of non-greasy characteristics on the hair which can be readily washed off with soap and water. However, it has been found that the films formed by these abietic esters are liquid films which do not have curl holding properties.
It has been proposed to use as the resin in an aqueous hair spray, an abietic acid condensate of a protein hydrolysate; and specifically the condensate sold commercially under the trademark "Lamepon PA-TR" which is a 30% aqueous solution of triethanolamine salt of a condensation product with abietic acid of a protein hydrolysate having an average molecular weight of about 400. The chemical and physical data included in the commercial literature of Lamepon PA-TR indicates that it has many properties which make it suitable for use in a hair dressing. The literature specifically states that for preparations such as hair lotions or hair sprays, which remain on the skin and hair for relatively long periods, as little as 0.1 to 0.2 percent of Lamepon PA-TR may be used in the formulation with good results. However, when it has been attempted to use the free carboxylic acid form of the condensate of Lamepon PA-TR as the major film-forming ingredient in an alcoholic hair-holding solution at the commercially and functionally desirable concentration of about 2 percent of condensate in absolute alcohol, it has been found that some of the condensate precipitates out of solution. This is surprising because no precipitate forms when the free carboxylic acid form of the condensate of Lamepon PA-TR is dissolved in absolute alcohol at a concentration of 20 percent.
In a hair dressing preparation intended for spray application, and particularly for aerosol spray application, the presence of any precipitate tends to clog the dispensing valve and impair the spray application. In addition, a precipitate in the spray solution tends to produce a cloudy deposit on the hair and thereby dulls the hair on application thereto.